This invention relates to an apparatus for removabley attaching a rigid plate to a support surface.
In a large number of the most diverse applications, it is necessary to mount a rigid plate on a support surface. This support surface can be a surface of a machine, an instrument, a piece of furniture, a building wall or the like. The plate can be used in particular for mounting anchoring fixtures, instrument parts, furniture items, etc. Depending on the application, the apparatus for attaching the plate to the support surface must be capable of absorbing varying loads.
In the case of sufficiently smooth support surfaces such as support surfaces of metal, glass, plastic, ground stone, wood, etc., flat adhesive joints have proved suitable. If a rigid plate is bonded flatly to the support surface, the adhesive joint usually has very high bonding resistance to being lifted perpendicularly from the support surface. If a tilting load acts on the plate, one edge of the plate is strongly pulled away from the fixing surface, while the opposite edge of the plate is braced as a tipping edge against the support surface. Particularly in the case of large and prolonged tilting loads, this can lead to gradual detachment of the adhesive joint, starting along the plate edge opposite the tipping edge. The long-time strength of the adhesive joint subjected to such tilting loads depends substantially on the creep characteristics of the adhesive. The worst creep tends to occur with adhesives of the type that do not impair the support surface and that if necessary can be removed from the support surface again without leaving traces.
One application of this attaching technique is the attaching of top-mounted items on a horizontal furniture top. Such top-mounted items are frequently exposed to considerable tilting loads, especially if they have a certain height. For example, it is known from a practical example of FIG. 8 of European Patent 0 457 957 A1 to which Steinhilber U.S. Pat. No. 5,282,427 corresponds how to mount a horizontal plate on the bottom end of a support post, this plate being placed flat on the surface of a desk top and fixed thereto by a stick-on hook and loop textile fastener. With this structure retrofitting of any type of writing desks and workbenches is possible by using a vertical support post. The vertical support post is suitable for holding various functional elements, for example the platform of a raised work stand, of a monitor holder, of a telephone arm or the like.
The attaching of the plate on the surface of the furniture top has the advantage compared with conventional clamping fixtures that the attaching structure is independent of the form of the furniture top and of the furniture. In particular, this type of attaching device can be used with furniture tops of any thickness and any edge shape, and even with furniture tops that do not project beyond the furniture body. Since the plate does not project beyond the border of the furniture top, the device for attaching the support post does not make it impossible to place the piece of furniture flush against another piece of furniture or against a room wall. The plate together with the support post can be removed from the surface of the furniture top without damaging the furniture top. For this purpose, the rigid plate is first separated in the region of the stick-on fastener. The portion of the stick-on fastener bonded to the furniture top can then be separated from the furniture top. Since this portion is flexible, it can be detached carefully from the surface of the furniture top without damaging that surface. This would be difficult if the rigid plate were bonded directly to the surface of the furniture top. This known apparatus for attaching the support column with a plate placed on the furniture top, especially a desk top, and joined thereto by a stick-on textile fastener, has proved eminently suitable.
If a tilting load is exerted by the support post on the plate, one edge of the plate will be pulled strongly away from the furniture surface in this case also, while the opposite edge of the plate will be braced as a tipping edge against the furniture top. Particularly during large and prolonged tilting loads, this can lead to gradual loosening of the stick-on fastener, starting along the plate edge opposite the tipping edge.